Why does my socket connect() fail after WSASetSocketSecurity()?

Question

I'm teaching a class where I'd like to show students how open a socket in C++ and read both http: and https: webpages under both Linux and Windows. The Linux version version was a breeze with OpenSSL . But under Windows using Microsoft's WSA socket library, I've only been able to read non-ssl pages. I cannot figure out how to get their WSASetSocketSecurity() function to work.

With the WSASetSocketSecurity call in the following code fragment commented out, I'm able to read http: (port 80) pages. I'm able to connect() to https: (port 443) hosts but attempts to send an HTML GET request and then recv() the page fail as expected with either nothing returned or a 400 bad request page from some servers because I haven't negotiated encryption.

Uncommenting the WSASetSocketSecurity call to guarantee encryption, the connect call always fails with WSAGetLastError = 10060 (Connection timed out) on both http: and https: pages.

Calling WSASetSocketSecurity but specifying allow insecure connections allows me to read http: pages but fails with https: pages in the same way as if WSASetSocketSecurity had not been called at all.

Fundamentally, I'm not able to turn on encryption and then connect and I don't know why.

I have tried experiments replacing the socket, connect and other calls with WSAxxx() versions, imagining there might be distinction similar to the way you have to do an SSL_connect call after the connect in Linux but that makes no difference. The only thing I can think of that I have not yet tried is authenticating the host using WSASetSocketPeerTargetName(), but it doesn't seem to me I should need to do that if all I want is an SSL link.

What am I missing here? Has anyone made this work?

   // Initialize the socket library.
   // wVersionRequested = 2.2 (current latest)

   WSADATA wsaData;
   int wsaStartupResult = WSAStartup( MAKEWORD( 2, 2 ), &wsaData );
   assert( wsaStartupResult == 0 );

   // Get the host address.

   ADDRINFOA *addressInfo;
   int addrInfoResult = getaddrinfo( url.Host, url.Service,
         nullptr, &addressInfo );
   assert( addrInfoResult == 0 );

   sockaddr *socketAddress = addressInfo->ai_addr;
   size_t socketAddressLength = addressInfo->ai_addrlen;
   PrintAddress( socketAddress, socketAddressLength );

   // Create a TCP/IP socket.

   SOCKET s = socket( AF_INET, SOCK_STREAM, IPPROTO_TCP );
   assert( s != INVALID_SOCKET );

   // Turn on SSL.

   SOCKET_SECURITY_SETTINGS security =
      {
      SOCKET_SECURITY_PROTOCOL_DEFAULT,
      SOCKET_SETTINGS_GUARANTEE_ENCRYPTION
      // SOCKET_SETTINGS_ALLOW_INSECURE
      };
/*
   int setSecurityResult = WSASetSocketSecurity( s,
         &security, sizeof( security ), nullptr, nullptr );
   assert( setSecurityResult == 0 );
*/

   // Connect to the host.

   int connectResult = connect( s, socketAddress, socketAddressLength );

   if ( connectResult != 0 )
      cerr << "Connect failed, WSAGetLastError = " << WSAGetLastError( ) << endl;
   assert( connectResult == 0 );

   // Send a GET message for the desired page.

   string getMessage = "GET ";
   getMessage += url.CompleteUrl;
   getMessage += " HTTP/1.1\r\nHost: ";
   getMessage += url.Host;
   getMessage += "\r\nConnection: close\r\n\r\n";

   cout << getMessage << endl;
   send( s, getMessage.c_str( ), getMessage.length( ), 0 );

   // Read from the socket until there's no more data.

   HANDLE Stdout = GetStdHandle( STD_OUTPUT_HANDLE );
   char buffer[ 10240 ];
   int bytes;
   DWORD length;

   while ( ( bytes = recv( s, buffer, sizeof( buffer ), 0 ) ) > 0 )
      WriteFile( Stdout, buffer, bytes, &length, nullptr );

   freeaddrinfo( addressInfo );
   closesocket( s );
   WSACleanup( );          

Answer 1

Your assumption that socket security turns on SSL / TLS is wrong. It is actually for enforcing use of IPsec protocol. See Winsock Secure Socket Extensions . If you need SSL/TLS then you should use Secure Channel (built-in Windows SSL/TLS library), OpenSSL or other dedicated library working on top of sockets.